Co-pending U.S. patent application Ser. No. 09/326,209, now U.S. Pat. No. 6,131,838, filed on Jun. 4, 1999, entitle SADDLE-BACK HAMMER TIP, is hereby incorporated by reference.
1. Field of Invention
The present invention relates to a mated hammer and hammer tip for releasable engagement with each other. In particular, to a hammer tip having a back portion comprised of two opposing shoulder-sections with a recessed section therebetween forming a saddle-back for releasable engagement with a face of the hammer formed by an upper and lower ledge and a raised center portion therebetween.
2. Background
In the art of construction of size reducing machines like rotary hammermills, tub grinders, vertical and horizontal feed machines, and the like, one of the most persistent problems faced by designers and operators of such equipment comprises properly releasably securing or engaging the hammer tips to the hammers. In the prior art, the sole method for attaching a hammer tip to a hammer involved merely inserting one or two threaded bolts through a bolt hole in the hammer tip and hammer then securing the bolt with a threaded nut. After a certain period of operational time, the hammer tip wears to the point of requiring replacement, which is accomplished through removal of the nut and bolt.
During this normal operation of the size reducing machine, however, the hammer tips come into frequent and violent contact with the product being size reduced. This places stress of all types from all directions on the hammer tip, and the hammer. Frequently, the striking force inflicted on the hammer tip begins to laterally torque, rotate, or twist the hammer tip, which eventually begins to peen the bolt holes. The twisting or rotational force on the hammer tip begins to force the bolts and bolt heads against the bolt hole introducing play. The additional play allows the bolt to move which will loosen the nut, or otherwise introduce movement between the hammer tip and the hammer. Once loosened, the play introduced will cause the bolt to break and prematurely disengage from the hammer, or otherwise come loose throwing the hammer tip into the machine.
A lose hammer tip in the machine can result in substantial damage to any exposed surface of the size reducing machine. In addition, with the hammer tip removed from the face of the hammer, the hammer quickly receives substantial unintended wear that can permanently damage the hammer. The replacement of a hammer comprises a significant detriment to the efficient operation of a size reducing machine. Furthermore, in most cases a hammer tip is thrown from the hammer well before the hammer tip needs replacement from normal wear.
Accordingly, a need exists in the art for better way of engaging hammer tips and hammers in a releasably securable manner.
An object of the present invention comprises providing a hammer and hammer tip combination for releasable mated engagement with each other that substantially reduces the chance of the hammer tip prematurely separating from the hammer.
These and other objects of the present invention will become apparent to those skilled in the art upon reference to the following specification, drawings, and claims.
The present invention intends to overcome the difficulties encountered heretofore. To that end, a mated hammer and hammer tip combination for releasable engagement are provided. The hammer includes a lower body portion for engagement with a rotor of a size reducing machine, and an upper body portion. The upper body portion of the hammer includes at least one bolt hole and a front face having a raised center section. The hammer tip includes a front face with a distally located working edge for debris impact, at least one bolt hole for receipt of a bolt to releasably engage the hammer and hammer tip, and a back having a plurality of protruding opposable members with a recessed section therebetween forming a saddle-back. The saddle-back in the back of the hammer tip releasable engages with the raised center section of the hammer.